Posted by MyGeneration on 2/12/2014 2:12:00 AM (view original):That's depressing, gillispie. It seems something I said once in a cynical moment is true:

This is not a basketball game played on computers; it is a computer game set in a basketball milieu. Or as you might put it: the basketball part of HD is merely window dressing.

the basketball part is definitely not window dressing... its just that certain aspects are more complex and detailed, and others are less. knowing how the sim works behind the scenes to some degree gives us some idea on where to dig deep, and where not to dig deep. i was simply pointing out a couple areas that one should not dig deep. other things are very complex, like what all factors into how many shots a player takes and how many go in. nobody really knows how that all works, we speculate, but there isn't enough reason to be convinced one way or another.

there's a great dilemma in making any simulation. if you make it too complex, with so many inputs, to allow the kind of control and detail the real sport has - its too confusing for the user. if you dumb it down too much, it doesn't behave realistically enough. personally, given the difficulty of this dilemma, i think its one of the areas where HD excels. yeah, offenses are kind of fudged and players don't really pass, but its not like passing has no value - the TSF decision (turnover shot fouled) flattens much of the actual passing into the common outcomes, which is a fairly reasonable way to approach it. thing is, you could simulate 5 passes and the probabilities of each outcome could be the same as it is represented in 1 simple equation. of course, its unlikely its really quite the same, but you always have to juggle the difficulty of balancing a complex system against the richness and detail added by making the system more complex.

like i said in the post where i mentioned that passing didn't really happen - you shouldn't let this discourage you too much. the sim is still rich and does a good job emulating most aspects of basketball. at first, it threw me for a loop, but i definitely understand why they did what they did, and how they limit the negative impact of not fully simulating certain parts of the game. its hard to walk through all that but if you do, i think you would also conclude they made pretty reasonable decisions there.

Ok correct me again if I'm wrong then but what it seems like, is on offense they run the simulation (however that works, I'll admit a huge deficiency when understanding how this sim runs exactly) and it determines the outcome of the play based on team averages and the variables like the type of offense and defense? Then assigns players to the outcomes based on their ratings and possibly distribution?

I guess what I'm now wondering is, is when the simulation is running are team ratings more responsible for scoring, and player ratings more to who actually gets the score?

There are team components and individual components to each equation. For example, team passing is a variable in the "Does the shot go in" equation but most of those components are individual player ratings.

Posted by a_in_the_b on 2/12/2014 12:50:00 PM (view original):Language! There are some words, oldave, that should NOT be used in public!

i did not actually say the name of hewhoshouldnotbenamed though... i was careful.

reminds me of plumpy... the original HD superstar.

back then the forums were alot more active (not to mention i dont think there were subcategories like today.... so youd get one thread with discussion of recruiting jucos, one thread of whether coach K was better than bob knight and another with thousands of pictures of scantily clad females) ,

anyways if you made any mention of plumpy, or pizza, or gorilla suits.... BAMMM, there he was with a witty reply. i always suspected he had some kind of program that alerted him any time certain keywords were uttered. either that, or he was god.

heres something that just occcured to me... what is the very first decision in the tree? gotta be "is there a turnover",.. right? but that would imply that turnovers are calculated off of some type of team average (and then distributed out to individual players based on some formula as to which players should be the most likely to commit TO. right?

or could it be that the first decision is "which guy on the offense is going to be in the "action spot"" and then it figures if that dude commits TO, or shoots, etc

I don't know how to value assists personally, but I have noticed that passing ratings do have an effect on A-to-TO ratio. A big who has bad passing ratings will get almost no assists. A big who has at least decent passing ratings will be closer to a 1-to-1 ratio.

The decision tree format is interesting. Does anyone have an opinion as to passing rating helping in keeping TO's down vs a press?

The decision tree is like my favorite think to talk about. I will respond later in more detail when uhh can get to a computer but the short answer is unless the first event is do they get the ball over 1/2 court the press seams pretty silly.

oldave - i believe the break logic is totally separate, or at least, largely separate. i tried, briefly, to find the knowledge base article that explains the logical steps, but i didn't see it. i wonder if they took it down? anyway, the first major decision was deciding who had the ball. this might sound crazy, it did to me, but hear me out (this is the non fastbreak decision). then, the engine has the infamous TSF decision - turnover, shot, fouled. at this junction, the turnover decision seems strange, because you'd think there would be a turnover decision before and after, but i think this turnover decision just figures out the chance of a turnover overall (as in, its strangely positioned but really does both things one would expect - has a team based component, which would factor into things like facing a press, and an individual component). it also figures the chance your team was fouled up to this point - again, most likely containing a team and individual component.

otherwise, the player is going to shoot. i can't remember how exactly players committing fouls worked into the whole thing, i don't think you had to have the ball to foul, but the way i explain it here, it sort of sounds like it. i think one of the outcomes from the shoot decision is you commit an offensive foul, which can go to any player? or maybe its only the shooter? i guess that would not throw things off too badly, given that offensive fouls by the non shooter are rare, and most fouls are committed on defense, in the other team's TSF decision.

after the shot, if its a make, they randomly decide to throw out an assist (its weighted) and then randomly assign it (also weighted). if its a miss, they rebound. then it starts again. all in all, a pretty simple flow of things, but many edge cases are left out, like inbounding, breaks, etc... which obviously are included in the game somehow. they talked about the free throw progression but it was unremarkable (what you would expect). i wish i could send you the write up from old admin, but i think that is a fairly decent summary.

I have spent a decent amount of time thinking about the decision tree. They released the whole tree for the baseball SIM about 5 years ago. It was fascinating and quite frankly, pretty good. The math geeks over there are pretty impressive and almost unilaterally very knowledgeable about the game. Other than a few minor squabbles and one unclear sentence we all more or less understand and agree with its logic. It’s nice to know how the game works.

When I started playing HD, I immediately looked for a similar document but couldn't find one. There is something in the NBA SIM FAQ but I don't think it is very detailed.

Through observation, logic, and my knowledge of the baseball event tree (assuming the programming is similar), I think the games calculations go in order something like this:

I kinda assume there are situational modifiers as well. Press teams probably get an advantage on made baskets, if there is a steal in the backcourt the new offensive team gets a bonus, stuff like that.

If yes, go to 2. If no, there is a turnover and start a possession for the opposing team.

2. Decide who shoots the ball.
I think this is an equation that factors in:

Offensive player’s distribution ratio for current players on the court
And
Offensive players “openness” value which is probably something ATH/SPD/IQ vs DEF/ATH/IQ/SPEED

3. Does the shooter turn the ball over?

(team passing probably plays a role in this)

If yes, start a new possession. In no, go to #4

4. Is it a 2 or 3 point shot?

Determined by +/- settings of player, defense and maybe ratio of shooter’s lp:per.

5. Is the shooter fouled?

If yes and a shooting foul, determine if FT is good.

If yes, start a new possession.

If no, jump to #7.

If yes and not a shooting foul, start over with #1.

If no, go to #6.

6. Does the shot go in?

(there might be a step in here like “determine what attributes are used for the shot”)

If yes, determine if there is an assist and start a new possession.
If no, determine if there is a block and go to #7.

7. Does the offense get the rebound?

If yes, determine if there is a tip in attempt or the offense resets and proceed back to #6 or #1.

If no, start a new possession.

Working with this as a base (assuming it’s reasonably close to being accurate), you can then attempt to analyze what factors are important in each event and look for trends like:
My slower PG tends to turn the ball over in the press
My high LP SF never misses a tip in
Etc….

This is a huge work in progress for me and I haven’t really had time to analyze and look for patterns other than “getting a feel”. In my defense, it’s only been 3 years, I am sure I will get around to it….

I welcome any critique, missed factors, or other general comments. I like to talk about this sort of stuff.

Seriously. Struggling with the concept of assists as window dressing. Probably mostly because I WANT it not to be window dressing.

So. Do we feel there is no instructive value in assist numbers?

One thing that jumped out at me with my Whittier wooden team this year is the horribly low number of assists we had in our losses.

We have a pretty good team. And are 22-4 with rpi about 10. But the 4 losses were incredibly ugly blowouts. They were all vs good teams. I happen to think I had more talent in each case. But impartial observers would probably say the talent level was pretty even.

Anyways. In those losses I think I averaged about 5 or 6 assisteses obviously. We had fewer made fg. But the rate of asset per made fg was very low also. Coincidence? Or am I confusing cause and effect or chicken and egg?

Joe. Do you have a spreadsheet or other program that allows you to easily scrape and figure things like "shooting percentage on tip ins" ?

I started working on it a while back, but got sidetracked and never got back to it.

I think I got frustrated over the issue that there seems to be no way to tell what position players assume when there is a double sswitch. I know that is not essential to much of the data one could glean from pbp. But it passed me off. I wanted to analyze whether swing men were more efficient at one position than aanother